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TerraMex · 08-15-2003, 12:57 PM

>What about the amperes? If the regulator can handle 5,
>shouldn't the transformer at least handle that many, maybe
>even 6?

the LM338 handles up to 5A of current . You can stick a circuit that draws 2A and it will still work perfectly. If your plan is to use the Comair fans dont think you'll have that much (5A) current draw.

Same for transformers. If it's rated for 5A , it can give you 5A maximum, but it wont be putting out those 5A unless you connect equiment that draws that current. Which is not the case here, if the fan's are rated for 1A each, the maximum draw will probably go near the 2A .

However, there are power units that dont use transformers :

http://www.mitedu.freeserve.co.uk/Ci.../Power/tps.htm

http://www.uco.es/~p62fugoj/supply5.htm

The problem is that they usually can't supply decent amp output (most rated for 15->50 mA).

>What do you mean by live? I will be attaching the box it is in to
>my case. What do I need to do to isolate it from live?

I mean anything that is in contact with electricity. You dont want a wire (or a solder point) touching the metal casing , which if it's connected to the computer case, will be grounded automaticaly.

>Can I use one relay for iwaki 15rt and the 24vdc variable ps?

Sure. It's a matter of wiring.

I have two, besides the one for the pump, i have a second (smaller) one for the PSU2 start. I decided to do this to prevent cutting in or doing wire soldering on them. So i change them in 2 minutes with new ones anytime. I'm a fan of "reversability".

>Does the fuse go before the relay or after? Before I assume.

Preferably before. I can go after, but if there's a surge, it might blow the relay , then the fuse.

But usually the relays are very resistant. My 10A one is, and it will never see more than 1A in his lifetime

(hopefully).

08-15-2003, 12:57 PM	#19
TerraMex Cooling Savant Join Date: Nov 2002 Location: Portugal, Europe Posts: 870	>What about the amperes? If the regulator can handle 5, >shouldn't the transformer at least handle that many, maybe >even 6? the LM338 handles up to 5A of current . You can stick a circuit that draws 2A and it will still work perfectly. If your plan is to use the Comair fans dont think you'll have that much (5A) current draw. Same for transformers. If it's rated for 5A , it can give you 5A maximum, but it wont be putting out those 5A unless you connect equiment that draws that current. Which is not the case here, if the fan's are rated for 1A each, the maximum draw will probably go near the 2A . However, there are power units that dont use transformers : http://www.mitedu.freeserve.co.uk/Ci.../Power/tps.htm http://www.uco.es/~p62fugoj/supply5.htm The problem is that they usually can't supply decent amp output (most rated for 15->50 mA). >What do you mean by live? I will be attaching the box it is in to >my case. What do I need to do to isolate it from live? I mean anything that is in contact with electricity. You dont want a wire (or a solder point) touching the metal casing , which if it's connected to the computer case, will be grounded automaticaly. >Can I use one relay for iwaki 15rt and the 24vdc variable ps? Sure. It's a matter of wiring. I have two, besides the one for the pump, i have a second (smaller) one for the PSU2 start. I decided to do this to prevent cutting in or doing wire soldering on them. So i change them in 2 minutes with new ones anytime. I'm a fan of "reversability". >Does the fuse go before the relay or after? Before I assume. Preferably before. I can go after, but if there's a surge, it might blow the relay , then the fuse. But usually the relays are very resistant. My 10A one is, and it will never see more than 1A in his lifetime (hopefully). __________________ "we need more cowbell." Last edited by TerraMex; 08-15-2003 at 01:02 PM.